To implement different policy and charging control on a different service data stream, the 3rd Generation Partnership Project (The 3rd Generation Partnership Project, 3GPP for short) defines a policy and charging control (Policy and Charging Control, PCC for short) system. The PCC system includes functional entities, such as a policy and charging rules function (Policy and Charging Rules Function, PCRF for short) entity, a policy and charging enforcement function (Policy and Charging Enforcement Function, PCEF for short) entity, a traffic detection function (Traffic Detection Function, TDF for short) entity, a bearer binding and event reporting function (Bearer Binding and Event Reporting Function, BBERF for short) entity, a subscription profile repository (Subscription Profile Repository, SPR for short), and an application function (Application Function, AF for short) entity.
In the PCC system, a set of event subscription mechanisms is defined. The AF may subscribe to an event provided by the PCRF; the PCRF further subscribes to a related event provided by entities such as the PCEF, the BBERF, and the TDF; and when the event occurs, the PCEF reports the event to the PCRF, and the PCRF further reports the event to the AF. The PCRF itself may also subscribe to an event provided by the PCEF, the BBERF, and the TDF as an input of a PCRF decision.
Events that are provided by the PCRF and can be subscribed to by the AF include: charging association information exchange, bearer loss, bearer release, bearer recovery, a change of an access network type, quota exhaustion of a prepaid user, a resource allocation success, a resource allocation failure, a change of a user equipment (User Equipment, UE for short) location, a change of a UE time zone, and the like.
Events that are provided by the PCEF and can be subscribed to by the PCRF include: a change of quality of service (Quality of Service, QoS for short), a change of a serving general packet radio service support node (Serving GPRS Support Node, SGSN for short), a change of an access network type, bearer loss, bearer recovery, quota exhaustion of a prepaid user, quota restoration of a prepaid user, Internet Protocol (Internet Protocol, IP for short) address allocation for a UE, IP address release for a UE, a change of an access gateway, a resource allocation success, a change of a UE location, a change of a UE time zone, and the like.
However, in an existing PCC system, an AF or a PCRF can acquire some events on a bearer plane but cannot acquire information about a packet. The information of the packet is significantly important for increasing transparency for a channel and for an AF, a service provider to which the AF belongs, in enhancing understanding of a pipeline transmission feature and correspondingly adjusting a service, improving user service experience, and locating a service fault cause. Therefore, how to acquire information about a packet relating to the user equipment by using a PCC system becomes a technical problem that needs to be solved currently.